Drobo hits the turbo-boost with newly launched 5N home NAS

New device ratchets up the speed with SSD caching and a much beefier CPU.

California-based Drobo today announced the launch of their new Drobo 5N five-bay NAS product. Ars has looked at Drobo's products before, and though we've been impressed with their ease of use, one thing that's always bothered us about the little black boxes has been their speed: for all their slickness, "fast" isn't traditionally a word you'd use to describe Drobo's consumer offerings.

With the 5N, Drobo hopes to change this. The new NAS contains two notable changes to the underlying hardware. Ars spoke with Drobo VP Mario Blandini, who informed us that the processor in the 5N has been beefed up from a dual-core ARM CPU to a "multicore" ARM CPU. More than anything else, this will boost throughput over the older models, as one core of the dual-core ARM CPU had been dedicated to running the Drobo's back-end operating system and BeyondRAID storage system, and the other core ran a virtualized Linux instance which handled all the file shares and front-end IO. Large network file transfers were handled by the front-facing virtualized Linux environment and would quickly peg the single available core of the split-brained CPU, even if the disks weren't being taxed. Older models rarely climbed past 30-40MB per second even in large streaming file transfers.

This shouldn't be a problem with the new model, which uses a faster ARM CPU with more cores available to service IO. In fact, this improvement in CPU is timely, because the other change to the Drobo 5N is the addition of an mSATA port and an optional SSD.

The SSD, if present, will hold the Drobo's operating system and BeyondRAID metadata, and then will be used for hot data caching, using methodology similar to Intel's Smart Response Technology. Frequently accessed blocks will be mirrored onto the SSD for faster reading; the SSD is also used as a write cache to catch incoming data quickly even if the spinning disks are busy. And if the 5N is purchased without an SSD initially, it still tracks file system usage data and can immediately begin mirroring its OS and its hot blocks to cache as soon as an SSD is installed. Any size SSD works, but Drobo has found through testing that 64GB is the ideal size—anything smaller hurts performance, and going bigger doesn't bring much additional benefit.

The 5N will share files via AFP to OS X boxes and SMB to Windows systems (with past boxes, NFS could be enabled by downloading and installing an add-on). The uprated CPU and internals should enable the 5N to saturate its gigabit Ethernet port, something previous-generation consumer Drobo products couldn't hope to do even under the best of circumstances.

The underlying storage technology of the Drobo, a containerized RAID-like striping and mirroring scheme called BeyondRAID (which we've examined in depth before) remains relatively unchanged, though Blandini informed us that Drobo has made substantial changes to the software stack to make the Drobo more efficient, and thus faster. The user-facing front-end environment is based on Wind River Linux, and if past Drobos are any indication, it will be quite friendly to enthusiast hacking (the good kind of hacking!) and custom add-on software.

Hardware wise, the new box looks very much like the Drobo FS, though in addition to the new internals, Drobo has added a two-year warranty, up from one year on its last-generation products (other new Drobo devices, like the mini and the direct-attached 5D, also carry two-year warranties). The 5N carries an MSRP of $599 with no disks and no mSATA SSD, a decrease of about $100 over the standard price of Drobo FS it is intended to replace.

Lee Hutchinson
Lee is the Senior Technology Editor at Ars and oversees gadget, automotive, IT, and culture content. He also knows stuff about enterprise storage, security, and manned space flight. Lee is based in Houston, TX. Emaillee.hutchinson@arstechnica.com//Twitter@Lee_Ars

Possibly a good idea, but the first thing I saw was the OCZ mSATA card. Scary based on their long history of problems.

I'd like to know the difference in throughput between the old Drobo (with dual-core) and new Drobo (with "multi" core), and how much does the SSD add on a practical level to performance? Does a 64GB SSD on a multi-TB RAID array really add much oomph?

The user-facing front-end environment is based on Wind River Linux, and if past Drobos are any indication, it will be quite friendly to enthusiast hacking (the good kind of hacking!) and custom add-on software.

Sadly, past history does not appear to apply. There is no DroboApp support presently on the 5N, at least per the product page. That's a deal-breaker for me.

Possibly a good idea, but the first thing I saw was the OCZ mSATA card. Scary based on their long history of problems.

I believe Drobo has a certified compatibility list; you'll want to specifically avoid Sandforce-based SSD's. A lot of 5D owners have been using the Crucial 64GB mSATA SSD.

FrisbeeFreek wrote:

I'd like to know the difference in throughput between the old Drobo (with dual-core) and new Drobo (with "multi" core), and how much does the SSD add on a practical level to performance? Does a 64GB SSD on a multi-TB RAID array really add much oomph?

Depends entirely on how good their caching system is and your usage patterns. Could be a huge benefit, could be a blip. We won't know until Ars or AnandTech gets a crack at it. I've heard that the new unit can saturate Gigabit Ethernet (it should, seeing as the 5D puts out even more impressive numbers on Thunderbolt); if true that would make it 2-6 times as fast as the old FS, but still trailing the Synology DS1512+ by a fair margin.

Possibly a good idea, but the first thing I saw was the OCZ mSATA card. Scary based on their long history of problems.

I'd like to know the difference in throughput between the old Drobo (with dual-core) and new Drobo (with "multi" core), and how much does the SSD add on a practical level to performance? Does a 64GB SSD on a multi-TB RAID array really add much oomph?

I would think so. On the enterprise side you might add a couple hundred gigs of SSD for some twenty TB of data on spinners - you'd be surprised about how little data is really active and generating big IO. Plus, what ever reads are coming off the SSD are freeing up your disks to service other IO.

It all depends on your usage pattern, obviously. SSD is not meant to really speed up your sequential throughput.

I break this down in great detail in my Drobo FS review. The short answer is that files are chopped up into chunks, and the chunks are spread out, either being mirrored to two disks, or striped to 3 or 4 disks. Different-sized HDDs don't so much matter to chunk redundancy, but it might affect how some of the striping works out as the disks fill. The system is constantly trying to stripe its data as wide as possible with its available capacity.

The biggest thing to keep in mind is that the drobo's usable capacity always set such that it can lose its largest drive (if 1-disk redundancy is turned on--if 2-disk redundancy is turned on, it's set so it can lose its two largest drives). So, if you have two 500GB drives and you add one 2TB drive, your usable capacity does not increase.

Drobo has a calculator where you can drag and drop various size disks around and see what the usable capacity is.

$599 is fairly expensive, but not ridiculously so for a small business NAS. Of course previous drobos have been hilariously slow so they were never viable alternatives. I wouldn't even consider purchasing a drobo until someone like storagereview does a thorough review. And even then I'd probably go with Synology.

That's for the 5D (this article is about the 5N). I'm not sure why the 5D is so much more when it looks like the 5N minus the network connectivity.

On a I guess related note, is the 5N actually available for purchase anywhere? I want to get one of these because I just got a nice check from my grandma (stop laughing!!!!!!), but even the official Drobo store doesn't look like it's selling them yet.

It's definitely not cheap but I guess most buyers would not want to be hassled with making their own NAS out of standard components. Still, for the price I would expect a few more features, especially the dropping of NFS support seems weird considering it's still using Linux to some extent. Which leads to another point that might be of some concern. Most folks in the know usually advise against using proprietary RAID configurations since if the hardware breaks down you'll have a hard time getting the data again. I guess you could buy a new drobo but what if it's no longer available or the implementation you had is no longer in use? A standard linux raid would just need another linux system supporting md. Also for long time storage wouldn't BSD be a better choice so as to have access to ZFS's copy-on-write's added data integrity?

As an aside, Lee I can't wait to see your review and a comparison with NAS units would be appreciated.

Second the motion of a review/comparison of NAS units. I've been looking at them a lot in the past few months, and I've been leaning towards a Synology 2 or 4 bay, but can't quite decide. Really want to set something up that can cover all my computers easily.

I still think these things should $300 devices maybe, not $600 dollar ones, at least if they really are targeted at 'home' users.

That said, I'd be very interested in a NAS/Multibay SATA enclosure roundup of all flavors, both networked, port-multiplier based, and raid card based, in use with BSD and Linux, either as hosts for the device or the hardware OS, with 4 - 8 HD bays.

Interesting indeed, first time I've been tempted by a Drobo though besides the speed problems the 5N hopefully fixes they have a history trouble with network media players.

I hope Drobo is putting more effort into the media streaming software that runs on it and not leaving it up to hackers to fill in the gaps, they are very far behind the likes of Thecus, QNAP and Synology in this area.

Possibly a good idea, but the first thing I saw was the OCZ mSATA card. Scary based on their long history of problems.

I believe Drobo has a certified compatibility list; you'll want to specifically avoid Sandforce-based SSD's. A lot of 5D owners have been using the Crucial 64GB mSATA SSD.

FrisbeeFreek wrote:

I'd like to know the difference in throughput between the old Drobo (with dual-core) and new Drobo (with "multi" core), and how much does the SSD add on a practical level to performance? Does a 64GB SSD on a multi-TB RAID array really add much oomph?

Depends entirely on how good their caching system is and your usage patterns. Could be a huge benefit, could be a blip. We won't know until Ars or AnandTech gets a crack at it. I've heard that the new unit can saturate Gigabit Ethernet (it should, seeing as the 5D puts out even more impressive numbers on Thunderbolt); if true that would make it 2-6 times as fast as the old FS, but still trailing the Synology DS1512+ by a fair margin.

Price-wise the DS1512+ is not really a comparable product - It's $799 vs $599. The Synology DS412+ would be the comparable product but it's actually still another $50 over the 5N - The DS413 could be compared, but it's $100 cheaper.

I find the entire Drobo design to honestly be stupid. Why do they have two OSes - it makes no sense and almost seems to be done just because.

I'm still craving an Ars Technica review of the Drobo 5D. I happen to have inside information that there's one waiting for me under the tree, and I'm very confident it will serve the purpose I have in mind for it, but I'm still interested in seeing an in-depth analysis.

I'm not too thrilled with having a hardware RAID. If the RAID controller goes belly up, you had better hope that the vendor still supports it and you can get a replacement. Moreover, I don't know if this supports copy-on-write, snapshots, or check-summing. If not, you're really not gaining much at this price point. I would have to agree with slogger -- a BSD based device (or Solaris) would be a better bet for data integrity. When it is all said and done, for enterprise grade storage, you need ZFS.

The SSD, if present, will hold the Drobo's operating system and BeyondRAID metadata, and then will be used for hot data caching, using methodology similar to Intel's Smart Response Technology. Frequently accessed blocks will be mirrored onto the SSD for faster reading; the SSD is also used as a write cache to catch incoming data quickly even if the spinning disks are busy.

(emphasis mine)

I start by immediately revealing my ignorance: isn't that a LOT of write activity for an SSD? Has the tech changed so much so quickly that life expectancy becomes adequate for such usage? I admit that I haven't followed the advances in SSD tech, except for price-per-gigabyte, but this usage sort of surprises me. It makes sense for speed, sure, but what about MTBF?

I'm not too thrilled with having a hardware RAID. If the RAID controller goes belly up, you had better hope that the vendor still supports it and you can get a replacement. Moreover, I don't know if this supports copy-on-write, snapshots, or check-summing. If not, you're really not gaining much at this price point. I would have to agree with slogger -- a BSD based device (or Solaris) would be a better bet for data integrity. When it is all said and done, for enterprise grade storage, you need ZFS.

You don't need ZFS for those features in the enterprise, though. Past a certain point, you're far better off with an enterprise NAS from NetApp or EMC or another one of the big enterprise storage players; when you're dealing with hundreds of terabytes, you need to begin factoring in vendor support and SLAs into the question, and a large home-built ZFS storage farm on BSD gear with no contract-backed SLA would terrify me.

Edited to elaborate: I'm a fan of ZFS. I like it. It's great, and it's got awesome features. SMBs and even large businesses might get a lot of value out of deploying it in a file server. But it doesn't necessarily bring anything new to the table at the enterprise level.

The SSD, if present, will hold the Drobo's operating system and BeyondRAID metadata, and then will be used for hot data caching, using methodology similar to Intel's Smart Response Technology. Frequently accessed blocks will be mirrored onto the SSD for faster reading; the SSD is also used as a write cache to catch incoming data quickly even if the spinning disks are busy.

(emphasis mine)

I start by immediately revealing my ignorance: isn't that a LOT of write activity for an SSD? Has the tech changed so much so quickly that life expectancy becomes adequate for such usage? I admit that I haven't followed the advances in SSD tech, except for price-per-gigabyte, but this usage sort of surprises me. It makes sense for speed, sure, but what about MTBF?

If all you do is read from them, they'll about last forever.

I can't wait for the new super-heating NAND that effectively makes write-wearing moot.

The SSD, if present, will hold the Drobo's operating system and BeyondRAID metadata, and then will be used for hot data caching, using methodology similar to Intel's Smart Response Technology. Frequently accessed blocks will be mirrored onto the SSD for faster reading; the SSD is also used as a write cache to catch incoming data quickly even if the spinning disks are busy.

(emphasis mine)

I start by immediately revealing my ignorance: isn't that a LOT of write activity for an SSD? Has the tech changed so much so quickly that life expectancy becomes adequate for such usage? I admit that I haven't followed the advances in SSD tech, except for price-per-gigabyte, but this usage sort of surprises me. It makes sense for speed, sure, but what about MTBF?

If all you do is read from them, they'll about last forever.

I can't wait for the new super-heating NAND that effectively makes write-wearing moot.

Well, that was my point - they aren't using the SSD as read-only, per the bolded sections of the article quote.

As an aside, Lee I can't wait to see your review and a comparison with NAS units would be appreciated.

Second the motion of a review/comparison of NAS units. I've been looking at them a lot in the past few months, and I've been leaning towards a Synology 2 or 4 bay, but can't quite decide. Really want to set something up that can cover all my computers easily.

Agree, but please, please include a review of UnRaid. It's very similar to this new Drobo but 1/5th the price.

- multiple odd-sized hdds- can use SSD for catche - use almost any old PC as the host chassis. - Each disk (apart from the parity drive) can be taken out and the files accessed on any PC- Only spins up the drive with the files you need, or the disk (+parity) you are writing to (saves a huge amount of energy over a Raid5 array. I ran a Raid5 array once. Never again. - no expensive RAID5 controller needed- more newbie friendly than FreeNas